Hi Chong.Feng,
As described in Chapter 16 of Programming Windows 8 Apps in HTML, CSS, and JavaScript, Visual Studio
can only debug one type of code at a time. Here’s the relevant excerpt:
When you hit that [JavaScript] breakpoint, step through the code using Visual Studio’s Step Into feature (F11 or Debug > Step Into). Notice that you do not step into the C# code, an effect of the fact that Visual Studio can debug either script or
managed (C#)/native (C++) code in one debugging session but unfortunately not both. Clearly, using some console output will be your friend with such a limitation.
so the breakpoint on javascript code can only work when you choose 'script only'.
Hope this helps, thanks.
Yanping Wang
MSDN Community Support | Feedback to us
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